| 摘要 |
<p>PURPOSE:To generate a margin recognizing signal for bar code reading correctly and to improve the performance of a bar code reader by measuring gap length for a guard bar, a margin, and a margin image generating area, and generating the margin recognizing signal for the bar reading when the measured value of the gap length is specific length. CONSTITUTION:A first detection circuit 2 which detects a white bar with width exceeding first prescribed width replying to the measured value of a gap measured value output circuit 1, a second detection circuit 4 which detects the white bar with the width less than second prescribed width, a third detection circuit 6 which detects a black bar with the width wider than the first prescribed width by a prescribed value, an AND circuit 8, and an OR circuit 10 are provided. The output signal of the OR circuit 10 is set as the margin recognizing signal for bar code reading. Thereby, it is possible to perform the reading of the bar code by obtaining correct recognition for the margin without depending on outside the specification or the accuracy of printing position of the bar code.</p> |
